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161.
We examined by Rietveld refinement of X-ray Diffraction patterns a series of 61 human and animal fossil bones in an age range from present time to Middle Triassic (around 245 Ma). This approach, supplemented by elemental analysis according to X-ray Fluorescence, has permitted to obtain a quantitative evaluation of the mineralogical phases in the specimens, thus allowing to reconstruct the mineralization process involved. Concerning the apatite phase, after adopting a monoclinic geometry for the unit cell, the method permits to determine with fair degree of precision the unit cell volume, which is found to decrease in relatively short geological times as a function of the fluorine substitution process for the hydroxyl group –OH. After excluding the role of a high-temperature fire treatment to the bones, it is found that a certain linear correlation may exist over the geological time scale involved between the age of the specimen and the average crystallite size. This observation permits to use the XRD pattern as an evaluation of the age of the fossil, although the stratigraphic observations, where available, remain as the main reliable source for dating such biomaterials. The uncertainty related to this age estimation may be hardly better than 15–20% in absolute, because of various assumptions involved in the XRD methodology used and in the variability of the burial environment that may be subjected to discontinuous changes over the very long time of deposition.  相似文献   
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During the several thousand years of human occupation in the Nasca drainage on the south coast of Peru, population movement into and out of the region impacted the formation and organization of society, as well as contributed to major cultural transformations. This study identifies foreign versus local individuals through the investigation of burial practices and strontium isotope analysis of human remains from the sites of La Tiza and Pajonal Alto dating from the Early Intermediate Period through the Late Intermediate Period (A.D. 1–1476). Of the ten samples analyzed, two individuals dating to the Middle Horizon were identified as foreigners. One of these individuals was buried in a new elite tomb type providing additional evidence that the Wari state incorporated Nasca into its realm. Two headless individuals, one dating to Middle Nasca with clear evidence of decapitation, and another dating to the Late Intermediate Period who was likely decapitated, were both locals. This suggests the practice of decapitation took place among local groups, and that the practice of decapitation and the use of heads as ritual items or trophies may have continued later in time than previously thought.  相似文献   
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The former Spanish Sahara is the last remaining colony in Africa. Most of the local people have been living in refugee camps in Algeria for the last 40 years and this situation has largely conditioned the archaeological research in the territory for a long time. In spite of the Saharawi Ministry of Culture in exile occasionally collaborating with European academic institutions for the study of its huge archaeological heritage, the training of local archaeologists or initiatives exclusively aimed at targeting the self-management of the Saharawi Archaeology are rarely carried out. This could be due to the difficulties in getting funds for long-term projects in this area, among other factors. However, today’s technological revolution has come to the desert including mobile telephones, televisions, computers and even an incipient Internet connection. At the same time, current digital technology has encouraged the development of new methods of documenting rock paintings, which might be appropriate and more accessible for the Saharawi technicians. This paper discusses the successful and failed aspects, as well as future perspectives, of a training course in rock art documentation intended for empowering local archaeologists who are living in very unfavourable circumstances.  相似文献   
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ABSTRACT

The presidential elections that brought the Workers’ Party (Partido dos Trabalhadores, or PT) to federal power represented a new moment for Brazil with the implementation of democratic, inclusive and sovereign policies. In the area of culture, the Ministry of Culture reclaimed a leadership role for the State and developed public policies with the critical participation of civil society. During the administrations of presidents Luis Inácio Lula da Silva and Dilma Rousseff, culture finally reached a new level. This article seeks to determine to what extent the cultural policies undertaken by these administrations promoted cultural citizenship. Based on a study of the course of cultural policies in the country, we argue that despite a conceptual and ideological orientation in this direction, the Ministry was unable to surpass certain barriers and overcome longstanding problems.  相似文献   
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ABSTRACT

The paper analyzes the static behavior and the seismic vulnerability of the “San Francesco ad Alto” building in Ancona (Italy), which is currently used as a Regional Headquarter of the Marche Region by the Italian Army and was formerly a monastery. The global static structural behavior and the dynamic properties have been evaluated using the Finite Element modeling technique, in which the nonlinear behavior of masonry has been taken into account by proper constitutive laws. The concepts of homogenized material and smeared cracking are used to evaluate the capacity of the monastery to withstand lateral loads together with the expected demands resulting from seismic actions (N2 method), using a nonlinear static analysis (pushover). The comparison of seismic demand and capacity confirms the susceptibility of these types of buildings to extensive damage and collapse, as frequently observed in similar buildings. This paper aims to point out that advanced numerical analyses can offer significant information on the understanding of the actual structural behavior of historical buildings. It is believed that the methodology and the overall conclusions of this case study are valid for many historical monasteries in Europe.  相似文献   
169.
The color patterns generally found on the façades of architecturally sensitive buildings have an adverse impact on their aesthetics, to the detriment of their identity and potential economic value. A quantitative and qualitative study was conducted of the perception of aesthetic decay in the limestone on a heritage building. The study assessed building aesthetics between two façade cleaning operations, conducted in 1984–1986 and 2006–2008. Based on the calculation of the final or total soiling index, by means of in situ lightness measurement and three architectural design variables, the color distribution of the façades was quantified in 2006 and a model was developed to monitor façade soiling over time. The proposed model, a tool for planning preventive façade maintenance on architecturally sensitive buildings, advocates for sustainable cleaning operations. Its premise that periodic cleaning should only be conducted in areas where the limestone is affected by aesthetic decay redounds to minimised intervention and lower building management costs.  相似文献   
170.
In this study, Monte Carlo (MC) simulations combined with energy dispersive X-ray fluorescence (EDXRF) spectroscopy have been used to characterize non-destructively a collection of Cu-based artifacts recovered from two archeological sites in southern Portugal: (a) the Chalcolithic E.T.A.R. site of Vila Nova de Mil Fontes and (b) the Middle Bronze Age site of Quinta do Estácio 6. The metal artifacts show a multilayered structure made up of three distinct layers: (a) brownish carbonate soil-derived crust, (b) green oxidized corrosion patina, and (c) bulk metal. In order to assess the reliability of the EDXRF-based Monte Carlo simulations to reproduce the composition of the alloy substrate in archeological bronze artifacts without the need to previously remove the superficial corrosion and soil derived patinas, EDXRF analysis together with scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS) was also performed on cleaned and patina-/crust-coated areas of the artifacts. Characterization of the mineralogical composition of the corrosion products in the surface patinas was further determined by means of X-ray diffraction (XRD). Results suggest that the adopted EDXRF/Monte Carlo protocol may represent a safe and fast analytical approach in the quantitative characterization of the bulk chemical composition of Cu-based metal artifacts even in the presence of fairly thick corrosion patinas and/or soil-derived encrustations at the surface of the archeological objects.  相似文献   
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